Analyte measurement device with a single shot actuator

ABSTRACT

An analyte and detecting apparatus includes a housing, an access door and a front end aperture. A module is positionable in the housing. A penetrating member is positioned in the module and upon launch passes through the front end aperture. An analyte sensor is positioned in the module. A penetrating member driver is configured to be coupled to the penetrating member. A mechanism is included that moves an arm coupled to the penetrating member driver into a launch position and allows motion of the penetrating member driver.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Ser. No. 12/696,298 filed Jan. 9, 2010, which claims the benefit of U.S. 61/148,761 filed Jan. 30, 2009. Said Ser. No. 12/696,298 is also a continuation in part of U.S. Ser. No. 11/536,720 filed Sep. 29, 2006, which is a continuation of U.S. Ser. No. 10/335,212 filed Dec. 31, 2002 (now U.S. Pat. No. 7,547,287 issued Jun. 19, 2009), U.S. Ser. No. 10/237,261 filed Sep. 5, 2002 (now U.S. Pat. No. 7,344,507 issued Mar. 18, 2008) and is a continuation in part of U.S. Ser. No. 10/127,395 filed Apr. 19, 2001 (now U.S. Pat. No. 7,025,774 filed Apr. 11, 2006). Said Ser. No. 12/696,298 is also related to U.S. Ser. No. 12/023,615 filed Jan. 31, 2008 (U.S. Pat. No. 7,6458,469 issued Jan. 19, 2010). All of the above applications are fully incorporated herein by reference.

BACKGROUND

1. Field of the Invention

This invention relates to analyte measurement devices, and more specifically, to an analyte measure device that has a disposable module with integrated sensors and penetrating members.

2. Description of the Related Art

Lancing devices are known in the medical health-care products industry for piercing the skin to produce blood for analysis. Biochemical analysis of blood samples is a diagnostic tool for determining clinical information. Many point-of-care tests are performed using whole blood, the most common being monitoring diabetic blood glucose level. Other uses for this method include the analysis of oxygen and coagulation based on Prothrombin time measurement. Typically, a drop of blood for this type of analysis is obtained by making a small incision in the fingertip, creating a small wound, which generates a small blood droplet on the surface of the skin.

Early methods of lancing included piercing or slicing the skin with a needle or razor. Current methods utilize lancing devices that contain a multitude of spring, cam and mass actuators to drive the lancet. These include cantilever springs, diaphragms, coil springs, as well as gravity plumbs used to drive the lancet. Typically, the device is pre-cocked or the user cocks the device. The device is held against the skin and the user, or pressure from the users skin, mechanically triggers the ballistic launch of the lancet. The forward movement and depth of skin penetration of the lancet is determined by a mechanical stop and/or dampening, as well as a spring or cam to retract the lancet. Such devices have the possibility of multiple strikes due to recoil, in addition to vibratory stimulation of the skin as the driver impacts the end of the launcher stop, and only allow for rough control for skin thickness variation. Different skin thickness may yield different results in terms of pain perception, blood yield and success rate of obtaining blood between different users of the lancing device.

Success rate generally encompasses the probability of producing a blood sample with one lancing action, which is sufficient in volume to perform the desired analytical test. The blood may appear spontaneously at the surface of the skin, or may be “milked” from the wound. Milking generally involves pressing the side of the digit, or in proximity of the wound to express the blood to the surface. The blood droplet produced by the lancing action must reach the surface of the skin to be viable for testing. For a one-step lance and blood sample acquisition method, spontaneous blood droplet formation is requisite. Then it is possible to interface the test strip with the lancing process for metabolite testing.

When using existing methods, blood often flows from the cut blood vessels but is then trapped below the surface of the skin, forming a hematoma. In other instances, a wound is created, but no blood flows from the wound. In either case, the lancing process cannot be combined with the sample acquisition and testing step. Spontaneous blood droplet generation with current mechanical launching system varies between launcher types but on average it is about 50% of lancet strikes, which would be spontaneous. Otherwise milking is required to yield blood. Mechanical launchers are unlikely to provide the means for integrated sample acquisition and testing if one out of every two strikes does not yield a spontaneous blood sample.

Many diabetic patients (insulin dependent) are required to self-test for blood glucose levels five to six times daily. Reducing the number of steps required for testing would increase compliance with testing regimes. A one-step testing procedure where test strips are integrated with lancing and sample generation would achieve a simplified testing regimen. Improved compliance is directly correlated with long-term management of the complications arising from diabetes including retinopathies, neuropathies, renal failure and peripheral vascular degeneration resulting from large variations in glucose levels in the blood. Tight control of plasma glucose through frequent testing is therefore mandatory for disease management.

Another problem frequently encountered by patients who must use lancing equipment to obtain and analyze blood samples is the amount of manual dexterity and hand-eye coordination required to properly operate the lancing and sample testing equipment due to retinopathies and neuropathies particularly, severe in elderly diabetic patients. For those patients, operating existing lancet and sample testing equipment can be a challenge. Once a blood droplet is created, that droplet must then be guided into a receiving channel of a small test strip or the like. If the sample placement on the strip is unsuccessful, repetition of the entire procedure including re-lancing the skin to obtain a new blood droplet is necessary.

What is needed is a device, which can reliably, repeatedly and painlessly generate spontaneous blood samples. In addition, a method for performing analytical testing on a sample that does not require a high degree of manual dexterity or hand-eye coordination is required. Integrating sample generation (lancing) with sample testing (sample to test strip) will result in a simple one-step testing procedure resulting in better disease management through increased compliance with self testing regimes.

There is a need for an analyte measurement device that has a disposable module with integrated sensors and penetrating members. There is a further need for an analyte measurement device, with integrated sensors and penetrating members, protected by a seal (foil) to preserve sterility and maintain a desiccated environment at the sensor. There is a further need for an analyte measurement device, with integrated sensors and penetrating members, that is protected by a seal (foil) to preserve sterility and maintain a desiccated environment at the sensor with radiation sterilization after sealing. There is yet another need for an analyte measurement device, with integrated sensors and penetrating members, with an actuator unit that accepts a disposable module and perforates the protective seal or foil during a loading sequence. Yet there is a further need for an analyte measurement device, with integrated sensors and penetrating members, with an actuator unit that accepts a disposable module and perforates the protective seal or foil during a loading sequence, with an actuator that grips the penetrating member during the loading sequence.

SUMMARY

An object of the present invention is to provide an analyte measurement device that has a disposable module with integrated sensors and penetrating members.

Another object of the present invention is to provide an analyte measurement device, with integrated sensors and penetrating members, that is protected by a seal (foil) to preserve sterility and maintain a desiccated environment at the sensor.

Yet another object of the present invention is to provide an analyte measurement device with integrated sensors and penetrating members, protected by a seal (foil) to preserve sterility and maintain a desiccated environment at the sensor with radiation sterilization after sealing.

A further object of the present invention is to provide an analyte measurement device, with integrated sensors and penetrating members, with an actuator unit that accepts a disposable module and perforates the protective seal or foil during a loading sequence.

Still another object of the present invention is to provide an analyte measurement device, with integrated sensors and penetrating members, with an actuator unit that accepts a disposable module and perforates the protective seal or foil during a loading sequence, with an actuator that grips the penetrating member during the loading sequence.

Yet another object of the present invention is to provide an analyte measurement device, with integrated sensors and penetrating members, with an actuator unit that accepts a disposable module and perforates the protective seal or foil during a loading sequence with an actuator that establishes electrical contact with the analyte sensor during the loading sequence.

Another object of the present invention is to provide an analyte measurement device, with integrated sensors and penetrating members, with an actuator unit that accepts a disposable module and perforates the protective seal or foil during a loading sequence with an actuator that unlocks the safety sweeper during the loading sequence.

Still another object of the present invention is to provide an analyte measurement device, with integrated sensors and penetrating members, with an actuator unit that accepts a disposable module and perforates the protective seal or foil during a loading sequence that has an actuator unit which uses virtual buttons to allow a larger display and more flexible user interface.

These and other objects of the present invention are achieved in, an analyte detecting apparatus with a housing, an access door and a front end aperture. A module is positionable in the housing. A penetrating member is positioned in the module and upon launch passes through the front end aperture. An analyte sensor is positioned in the module. A penetrating member driver is configured to be coupled to the penetrating member. A mechanism is included that moves an arm coupled to the penetrating member driver into a launch position and allows motion of the penetrating member driver.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates one embodiment of an analyte detecting apparatus of the present invention where an access door is open and a sensor module inserted into a cradle ready for loading.

FIG. 2 illustrate an embodiment of an analyte detecting apparatus of the present invention with a seal in place relative to a module in the housing.

FIG. 3 illustrates an embodiment of the present invention with a module with a foil removed to show relative locations of the penetrating member and glucose sensor.

FIG. 4 illustrates an embodiment of a penetrating member launcher mechanism with a disposable module, without a seal, in a load position.

FIG. 5 illustrates an embodiment of the present invention after sensing and with a sweeper handle retracted.

FIG. 6 is an exploded view of the flat coil driver.

FIG. 7 is a diagrammatic view illustrating a controlled feed-back loop.

DETAILED DESCRIPTION

In one embodiment of the present invention, a mechanism is provided for utilizing an integrated disposable that contains both a penetrating member and glucose sensor (module). Upon loading a sensor module, a user closes the access door, presses a finger against the front end aperture, and initiates the penetrating member fire sequence. A small wound is created in the finger and the resulting blood is captured by the glucose sensor and analyzed. The resulting blood glucose reading is presented to the user on a display, including but not limited to an LCD display on the top of the device.

In one embodiment, the disposable glucose sensor module is based on an injection molded plastic body that cradles a penetrating member and holds a glucose sensor. The penetrating member and sensor can be protected for sterility and for humidity protection by means, as an non-limiting example, of an aluminum foil that is bonded to the top, end, and bottom surfaces of the plastic body. FIG. 2 shows a module with foil in place. FIG. 3 illustrates a module with the foil removed and illustrates the relative locations of the penetrating member and glucose sensor.

In one embodiment of the present invention, an analyte detecting apparatus 10 includes a housing 12, an access door 14 and a front end aperture 16. A module 18 is positionable in the housing 12. A penetrating member 22 is positioned in the module 18 and upon launch passes through the front end aperture 16. An analyte sensor 24 is positioned in the module 18. A penetrating member driver 26, also known as a launcher mechanism, is configured to be coupled to the penetrating member 22. A mechanism is included that moves an arm coupled to the penetrating member driver 26 into a launch position and allows motion of the penetrating member driver.

As illustrated in FIG. 1, a launcher mechanism is illustrated with the access door 14 open and a sensor module 18 inserted into its cradle ready for loading, with the seal not shown. As the access door 14 is closed, an internal lever moves the sweeper arm into the fire or launch position, allowing free motion of the penetrating member driver 26. As the access door 14 is further closed, the module 18 is swept past cutting blades 28 that remove a protective seal 31 from the end of the module 18 and exposing a sensor port and sensor electrical contacts for use.

As the access door 14 is further closed, the module 18 is forced over a shield structure that pierces the seal over the penetrating member 22 and folds the seal away from the penetrating member driver 26. As the access door 14 is further closed, the module 18 is pressed onto a gripper 30 that is attached to the penetrating member driver 26, forcing the penetrating member 22 into engagement with the gripper 30. As the access door 14 is further closed, a return spring 32 is compressed and, finally, a limit switch 34 is activated indicating that the module 18 is fully seated and the penetrating member 22 is gripped and ready to fire. When the user releases the access door 14 the return spring 32 lifts the module 18 slightly allowing free motion of the gripper 30 during the actuation sequence.

In FIG. 1, the front end aperture 16, where the finger presses, the analyte sensor and penetrating member 22 can be seen in the end of the unit. This front end aperture 16 is part of a resilient “front end” structure that locates the finger and promotes spontaneous blood production. Results from the glucose analysis and actuator status are presented on a display on the top of the unit. By way of illustration, and without limitation, in one embodiment, a display 36 can be a 26.5 mm×39.0 mm LCD display. The display 36 may be configured as a touch screen and would then be able to also act as the “fire” button and as the “depth increase” and “depth decrease” buttons.

As illustrated in FIG. 1, an actuator button 38, or ribbed slider handle, is seen on the right front side of the housing 12. This button 38 is connected to a sweeper arm 40 and projects away from the housing 12 when the sweeper arm 40 is in the “fire” position as a reminder to the user that the penetrating member driver 26 is capable of firing a penetrating member 22. After firing the penetrating member 22, the only action required of the user is to slide the actuator button 38 back into the parked or “safety” position.

At the time of the next use of the apparatus 10, the access door 14 is opened and the used module 18 (if present) is removed and replaced by an unused disposable module 18. The access door 14 can then be closed, repeating the cycle.

As a non-limiting example, In one embodiment, the size of the penetrating member driver 26 is approximately 58 mm wide×75 mm long×20 mm thick (at the display). As a non-limiting example, the size of the module 18 is approximately 8.5 mm wide×31 mm long×3.75 mm thick, and the weight of the disposable sensor module 18 is approximately 0.53 gm.

As illustrated in FIG. 4, one embodiment of a penetrating is illustrated of a penetrating member launcher mechanism with a disposable module 18, without a seal, in a load position is shown.

FIG. 5 illustrates an embodiment of the present invention after sensing and with the sweeper handle arm 40.

Referring to FIG. 6, a flat coil lancet driver 325 is illustrated which has a main body housing 326 and a rotating frame 327. The rotating frame 327 pivots about an axle 328 disposed between a base 329, a top body portion 330 of the main body housing 326 and disposed in a pivot guide 331 of the rotating frame 327. An actuator arm 332 of the rotating frame 327 extends radially from the pivot guide 331 and has a linkage receiving opening 333 disposed at an outward end 334 of the actuator arm 332. A first end 335 of a coupler linkage 336 is coupled to the linkage receiving opening 333 of the actuator arm 332 and can rotate within the linkage receiving opening 333. A second end 337 of the coupler linkage 336 is disposed within an opening at a proximal end 338 of a coupler translation member 341. This configuration allows circumferential forces imposed upon the actuator arm 332 to be transferred into linear forces on a drive coupler 342 secured to a distal end 343 of the coupler translation member 341. The materials and dimensions of the drive coupler 342 can be the same or similar to the materials and dimensions of the drive coupler 342 discussed above.

FIG. 7 illustrates the operation of a feedback loop using a processor. The processor 60 stores profiles 62 in non-volatile memory. A user inputs information 64 about the desired circumstances or parameters for a lancing event. The processor 60 selects a driver profile 62 from a set of alternative driver profiles that have been preprogrammed in the processor 60 based on typical or desired tissue penetration device performance determined through testing at the factory or as programmed in by the operator. The processor 60 may customize by either scaling or modifying the profile based on additional user input information 64. Once the processor has chosen and customized the profile, the processor 60 is ready to modulate the power from the power supply 66 to the lancet driver 68 through an amplifier 70. The processor 60 measures the location of the lancet 72 using a position sensing mechanism 74 through an analog to digital converter 76. Examples of position sensing mechanisms have been described in the embodiments above. The processor 60 calculates the movement of the lancet by comparing the actual profile of the lancet to the predetermined profile. The processor 60 modulates the power to the lancet driver 68 through a signal generator 78, which controls the amplifier 70 so that the actual profile of the lancet does not exceed the predetermined profile by more than a preset error limit. The error limit is the accuracy in the control of the lancet.

After the lancing event, the processor 60 can allow the user to rank the results of the lancing event. The processor 60 stores these results and constructs a database 80 for the individual user. Using the database 80, the processor 60 calculates the profile traits such as degree of painlessness, success rate, and blood volume for various profiles 62 depending on user input information 64 to optimize the profile to the individual user for subsequent lancing cycles. These profile traits depend on the characteristic phases of lancet advancement and retraction. The processor 60 uses these calculations to optimize profiles 62 for each user. In addition to user input information 64, an internal clock allows storage in the database 80 of information such as the time of day to generate a time stamp for the lancing event and the time between lancing events to anticipate the user's diurnal needs. The database stores information and statistics for each user and each profile that particular user uses.

In addition to varying the profiles, the processor 60 can be used to calculate the appropriate lancet diameter and geometry necessary to realize the blood volume required by the user. For example, if the user requires a 1-5 micro liter volume of blood, the processor selects a 200 micron diameter lancet to achieve these results. For each class of lancet, both diameter and lancet tip geometry, is stored in the processor to correspond with upper and lower limits of attainable blood volume based on the predetermined displacement and velocity profiles.

Expected variations or differences in the results are contemplated in accordance with the objects and practices of the present invention. It is intended, therefore, that the invention be defined by the scope of the claims which follow and that such claims be interpreted as broadly as is reasonable. 

What is claimed is:
 1. An analyte detecting apparatus, comprising: a housing with an access door and a front end aperture; a module positionable in the housing; a protective seal at an end of the module; a penetrating member positioned in the module and upon launch passes through the front end aperture; an analyte sensor positioned in the module; a penetrating member driver configured to be coupled to the penetrating member; wherein upon a first further closure of the access door the module is swept past a cutting mechanism that removes the protective seal from the end of the module and exposes a sensor port for use.
 2. The apparatus of claim 1, wherein upon the first further closure of the access door the module is swept past a cutting mechanism that removes the protective seal from the end of the module and exposes and sensor electrical contacts.
 3. The apparatus of claim 1, wherein upon a second further closure of the access door the module is forced over a shield structure that pierces a seal over the penetrating member.
 4. The apparatus of claim 3, wherein upon the second further closure of the access door the module is forced over the shield structure that pierces the seal over the penetrating member and folds the seal away from the penetrating member driver.
 5. The apparatus of claim 1, wherein application of pressure from a finger on the front end aperture begins a first sequence of the penetrating member.
 6. The apparatus of claim 1, further comprising: a display positioned at an exterior of the housing that displays a reading associated with analyte measurement.
 7. The apparatus of claim 1, wherein the module is an injection molded plastic body that cradles the penetrating member and holds the analyte sensor.
 8. The apparatus of claim 1, further comprising: a penetrating member engagement member that engages the penetrating member to the penetrating member driver.
 9. The apparatus of claim 1, further comprising: a spring that is compressed as the access door closes.
 10. The apparatus of claim 9, further comprising: a switch that indicates when the module is fully seated and the penetrating member is gripped and ready to launch.
 11. The apparatus of claim 10, wherein when the access door is released, the spring lifts the module and allows free motion of the penetrating member engagement member during a penetrating member actuation sequence.
 12. The apparatus of claim 1, further comprising: an activation element positioned at an exterior of the housing and configured to be coupled with a sweeper arm. 